The Great Nagisa V2

Nagisa, a monster hunter, has one secret she's never told anyone. She actually has a twin sister named Fubuki, who lives in the underworld. One day, after a particularly ticklish job, Nagisa is approached by her sister, who asks for her help to conquer the Underworld! Unfortunately for Nagisa, and her sister, it doesn't matter where they go, they always find themselves at the mercy of some tickler.